Preheat the oven to 350 degrees F. Spray a 13-by-9-inch baking dish with nonstick cooking spray.
Mix the coconut and condensed milk in a bowl until well combined. Spread the mixture evenly in the prepared baking dish. Bake until the coconut is completely browned with dark and crispy edges, about 20 minutes.
Cool slightly, then cut into squares. Serve warm or at room temperature.